Radio communication systems are well known in the communication art. In such systems, communication devices such as radios communicate with each other over radio frequencies. Radio communication systems allow people to communicate over long distances, while still allowing communication device users mobility.
Many users of communication systems especially portable communication device users work in hazardous environments. For example, firemen work in smoke-filled environments on a daily basis, and use portable radios in order to communicate with each other during a fire situation. Another example are chemical industry employees who work in or near gaseous environments which can sometimes be life-threatening.
A need exists for a communication system having communication devices which can detect the presence of dangerous environmental conditions such as smoke, dangerous gases, etc., and can automatically alert other communication devices of the condition.
Present day technology in the field of environmental condition protection has not addressed the need for protecting a user who is mobile, and who requires communication system supervision in case of a life threatening problem to the user. Presently, pocket sized portable alarms which can detect the presence of hazardous environmental levels are available, but they do not have the capabilities of transmitting the hazardous condition information to a central location for supervision and monitoring. Other presently available monitoring systems include "hard wired" systems which are part of computerized networks which allow for the environmental monitoring at fixed locations of a building. These systems tend to be expensive to install due to the wiring which is required in order to implement the system, and tend not to be flexible once the system is installed since this require rerouting of existing cables. These hard wired systems also tend to be difficult to expand due to the issues of interfacing to pre-existing cables.